/*
*    Qizx/open 3.0 beta
*
* This code is the open-source version of Qizx.
* Copyright (C) 2004-2009 Axyana Software -- All rights reserved.
*
* The contents of this file are subject to the Mozilla Public License 
*  Version 1.1 (the "License"); you may not use this file except in 
*  compliance with the License. You may obtain a copy of the License at
*  http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
*  WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
*  for the specific language governing rights and limitations under the
*  License.
*
* The Initial Developer of the Original Code is Xavier Franc - Axyana Software.
*
*/
using System;
using EvaluationException = System.Qizx.Api.EvaluationException;
using QName = System.Qizx.Api.QName;
using BasicNode = System.Qizx.Xdm.BasicNode;
using EvalContext = System.Qizx.XQuery.EvalContext;
using ExprDisplay = System.Qizx.XQuery.ExprDisplay;
using Focus = System.Qizx.XQuery.Focus;
using ModuleContext = System.Qizx.XQuery.ModuleContext;
using XQValue = System.Qizx.XQuery.XQValue;
using SingleNode = System.Qizx.XQuery.Dt.SingleNode;
namespace System.Qizx.XQuery.Op
{
	
	/// <summary> class NodeConstructor:</summary>
	public abstract class NodeConstructor:Expression
	{
		public override int Flags
		{
			get
			{
				return flags;
			}
			
		}
		public const int DIRECT = 0x200;
		
		public Expression[] contents;
		protected internal int flags;
		
		public virtual void  addItem(Expression item)
		{
			contents = addExpr(contents, item);
		}
		
		public override Expression Child(int rank)
		{
			return rank < contents.Length?contents[rank]:null;
		}
		
		public override Expression addChild(Expression child, QName name)
		{
			addItem(child);
			return child;
		}
		
		public override void  Dump(ExprDisplay d)
		{
			d.header(this);
		}
		
		public virtual bool resolvesToConstructor()
		{
			return true;
		}
		
		public override Expression StaticCheck(ModuleContext context, int flags)
		{
			for (int e = 0, E = contents.Length; e < E; e++)
			{
				contents[e] = context.staticCheck(contents[e], 0);
				if (UpdatingExpr.isUpdating(contents[e]))
					this.flags |= UPDATING;
			}
			return this;
		}
		
		public virtual void  setDirect()
		{
			flags |= DIRECT;
		}
		
		public override XQValue eval(Focus focus, EvalContext context)
		{
			BasicNode node = EvalAsNode(focus, context);
			return (node == null)?System.Qizx.XQuery.XQValues.Empty:new SingleNode(node);
		}
	}
}